Wafer processing apparatus with a rotatable table

ABSTRACT

The disclosure relates to a wafer processing apparatus for processing wafers with a rotatable table provided with a support constructed and arranged to support a removable holder for storing a plurality of wafers. A drive assembly may be provided to provide a rotary movement to the rotatable table around a vertical axis perpendicular to the table; and, a supply line may be constructed and arranged to supply utilities to the rotatable table. The drive assembly may be controlled and configured to create the rotary movement of the table in a clockwise and/or an anticlockwise direction to avoid breakage of the supply line.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent Application Ser. No. 63/127,589 filed Dec. 18, 2020 titled WAFER PROCESSING APPARATUS WITH A ROTATABLE TABLE, the disclosure of which is hereby incorporated by reference in its entirety.

FIELD

The present disclosure generally relates to a wafer processing apparatus for processing wafers. The apparatus comprising a rotatable table provided with a support constructed and arranged to removably support a holder for holding a plurality of wafers; and, a drive assembly to provide a rotary movement to the rotatable table around a substantial vertical axis substantially perpendicular to the table.

BACKGROUND

Wafer cassettes e.g. front-opening unified pods (FOUPs) or wafer boats may be used as a holder for holding and moving a plurality of wafers in or to a wafer processing apparatus. The wafer processing apparatus may comprise a rotatable table provided with a support constructed and arranged to removable support the holder so as to be able to move the removable holder by rotation.

It may be necessary to provide utilities such as fluids or electricity to the rotatable table.

SUMMARY

This summary is provided to introduce a selection of concepts in a simplified form. These concepts are described in further detail in the detailed description of example embodiments of the disclosure below. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

It may be an object to provide a wafer processing apparatus with an improved way of providing utilities to the rotatable table.

To that end, there may be provided a wafer processing apparatus for processing wafers comprising a rotatable table provided with a support constructed and arranged to removably support a holder for holding a plurality of wafers; and, a drive assembly to provide a rotary movement to the rotatable table around a substantial vertical axis substantially perpendicular to the table. The apparatus may be provided with a supply line to supply a utility to the rotatable table. The drive assembly may be controlled and configured to create the rotary movement of the table in two directions, clockwise and anticlockwise, to avoid breakage of the supply line.

For purposes of summarizing the invention and the advantages achieved over the prior art, certain objects and advantages of the invention have been described herein above. Of course, it is to be understood that not necessarily all such objects or advantages may be achieved in accordance with any particular embodiment of the invention. Thus, for example, those skilled in the art will recognize that the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught or suggested herein without necessarily achieving other objects or advantages as may be taught or suggested herein.

Various embodiments are claimed in the dependent claims, which will be further elucidated with reference to an example shown in the figures. The embodiments may be combined or may be applied separate from each other.

All of these embodiments are intended to be within the scope of the invention herein disclosed. These and other embodiments will become readily apparent to those skilled in the art from the following detailed description of certain embodiments having reference to the attached figures, the invention not being limited to any particular embodiment(s) disclosed.

BRIEF DESCRIPTION OF THE FIGURES

It will be appreciated that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of illustrated embodiments of the present disclosure.

FIG. 1 shows a schematic top/see through view of an example of a wafer processing apparatus according to an embodiment;

FIG. 2 shows a schematic top/see through view of a cassette handling space of the example of the wafer processing apparatus of FIG. 1;

FIG. 3 shows a schematic side view of the example of FIG. 1;

FIG. 4 depicts a part of the cassette storage carousel 18 of FIGS. 1 to 3;

FIG. 5 shows a perspective view of a wafer processing apparatus according to an embodiment; and,

FIG. 6 shows a schematic top view of the example of a wafer processing apparatus according to FIG. 5.

DETAILED DESCRIPTION

In this application similar or corresponding features are denoted by similar or corresponding reference signs. The description of the various embodiments is not limited to the example shown in the figures and the reference numbers used in the detailed description and the claims are not intended to limit the description of the embodiments, but are included to elucidate the embodiments by referring to the example shown in the figures.

Although certain embodiments and examples are disclosed below, it will be understood by those in the art that the invention extends beyond the specifically disclosed embodiments and/or uses of the invention and obvious modifications and equivalents thereof. Thus, it is intended that the scope of the invention disclosed should not be limited by the particular disclosed embodiments described below. The illustrations presented herein are not meant to be actual views of any particular material, structure, or device, but are merely idealized representations that are used to describe embodiments of the disclosure.

As used herein, the term “wafer” may refer to any underlying material or materials that may be used, or upon which, a device, a circuit, or a film may be formed. The wafer may be of any material including semiconductor materials like silicon.

In the most general terms the present disclosure provides a wafer processing apparatus 10 for processing wafers, of which examples are shown in FIGS. 1-6. The apparatus 10 may comprise a cassette handling space 26. The cassette handling space 26 may be provided with a cassette storage 14 configured to store a plurality of wafer cassettes 16 provided with a plurality of wafers. The cassette handling space 26 may be provided with a cassette handler 28 configured to transfer wafer cassettes 16 between the cassette storage 14 and a wafer transfer position 24. The cassette handler 28 may be embodied as a single cassette handler 28.

The wafer processing apparatus 10 may comprise a wafer handling space 30. The wafer handling space 30 may be provided with a wafer handler 32 configured to transfer wafers between a wafer cassette 16 in the wafer transfer position 24 and a wafer boat in a wafer boat transfer position.

The wafer processing apparatus may comprise an internal wall 20 separating the cassette handling space 26 and the wafer handling space 30. The internal wall 20 may be provided with a wafer transfer opening 22 adjacent the wafer transfer position 24 for a wafer cassette 16 from or to which wafers are to be transferred. The cassette storage 14 may comprise two cassette storage carousels 18.

In an embodiment, the two cassette storage carousels 18 may overhang the internal wall 20 and the wafer handling space 30. By overhanging the internal wall 20 and the wafer handling space 30, a footprint of the wafer processing apparatus 10 may be reduced. This means that the amount of expensive floor area needed to accommodate the wafer processing apparatus is reduced and thus the overall costs for the wafer processing apparatus 10 is also reduced.

In an embodiment, the wafer processing apparatus 10 may be provided with a substantially rectangular footprint having two opposite short sides defining a width 36 of the wafer processing apparatus 10 and having two opposite long sides defining a length 38 of the wafer processing apparatus 10. The width 36 of the wafer processing apparatus 10 may be around 2.2 meter or less. The length 38 of the wafer processing apparatus 10 may be 5 meter or less, preferably 4 meter or less.

By having a substantial rectangular footprint, multiple wafer processing apparatus 10 may be arranged adjacent to each other, thus making optimal use of available floor area. Adjacent wafer processing apparatus with rectangular footprints may have no unused space in between them. A width 36 of less than 2.2 meter is beneficial in view of interchangeability with other vertical batch furnace assemblies, for example from other manufacturers/brands. A length 38 of 5 meter or less, preferably 4 meter or less, is beneficial for reducing the footprint altogether.

In an embodiment, the cassette storage 14 may be configured to store 20 to 60 wafer cassettes 16. In an embodiment, the wafer cassettes 16 may be embodied as Front Opening Unified Pods (FOUPs). FOUPs are considered standard enclosures for wafers in the industry. Using FOUPs is advantageous for exchangeability of the wafer cassettes between the wafer processing apparatus 10 and other wafer processing machines.

In an embodiment, the two cassette storage carousels 18, the cassette handler 28 and the wafer handler 32 may be provided in a space between a bottom side 40 of the wafer processing apparatus 10 and a horizontal plane 42 at a height 44 of around 2.8 meter above the bottom side 40. The wafer processing apparatus 10 may have a removable top cover 46 extending above the horizontal plane 42 at the height 44 of around 2.8 meter above the bottom side 40. The top cover 46 may close off a top opening 80 in a top wall 82 of the wafer processing apparatus 10 through which top opening 80 wafer cassettes 16 may extend which are placed at a top platform stage 70 of at least one cassette storage carousel 18 of the two cassette storage carousels 18.

By ensuring that the two cassette storage carousels 18, the cassette handler 28 and the wafer handler 32 remain below a height 44 of around 2.8 meter, these parts remain within reach of an operator for maintenance and can be transported in the normal operating position through the standard clean room doors. Furthermore, these parts can be shipped in an assembled state, without the need to split them for shipping in standard size containers. This means that the wafer processing apparatus 10 can be shipped in one piece and may therefore be assembled in the factory of the manufacturer of the wafer processing apparatus 10. Thus no extensive assembling on site may be needed which reduces the cost of installing the wafer processing apparatus 10.

In an embodiment, the wafer processing apparatus 10 may further comprise at least one cassette in-out port 48. The at least one cassette in-out port 48 provides the entrance to and the exit from the wafer processing apparatus 10, for the exchange of wafer cassettes 16 between the wafer processing apparatus 10 and the outside world. The at least one cassette in-out port 48 may be provided in a wall 84 bounding the cassette handling space 26. Said wall 84 may be at or near the short side of the substantially rectangular footprint of the wafer processing apparatus 10. The cassette handler 28 may be configured to transfer wafer cassettes 16 between the cassette storage 14, the wafer transfer position 24, and the at least one cassette in-out port 48. Such a cassette handler 28 can handle all of the wafer cassette transfers within the cassette handling space 26. By using only one cassette handler 28, space which would otherwise be occupied by additional cassette handlers can be used for other purposes. Thus the size of the wafer processing apparatus 10 may be further reduced, or the wafer processing apparatus 10 may store even more wafer cassettes 16.

In an embodiment, the cassette handler 28 may be provided with a cassette handler arm 50, and a lift mechanism 52 configured to reach wafer cassettes 16 at different vertical heights within the cassette storage 14. In an embodiment, the wafer processing apparatus 10 may further comprise a cassette door opener device 54. The cassette door opener device 54 may be placed at or near the wafer transfer position 24. The cassette door opener device may be configured to open a cassette door of a wafer cassette 16 which is placed in the wafer transfer position 24. The cassette door opener device 54 may thus automatically open a cassette door of a wafer cassette 16 which is placed in the wafer transfer position 24.

The wafer processing apparatus 10 may be a part of a production process in a clean room. The wafer cassettes 16 provided to and coming from the wafer processing apparatus 10 may therefore be used in other wafer processing machines. Having the ability to automatically open a cassette door of these wafer cassettes 16, makes it possible to use wafer cassettes which are provided with these cassette doors. This increases the exchangeability of wafer cassettes 16 between the wafer processing apparatus 10 and these other wafer processing machines.

In an embodiment, the wafer processing apparatus 10 may further comprise a process chamber 56, 58 configured to process wafers.

In an embodiment, each cassette storage carousel 18 functioning as a rotatable table may comprise a number of platform stages 70. The platform stages 70 may support a number of wafer cassettes 16 each functioning as a removable holder for holding a plurality of wafers outside the process chamber 56, 58. The wafer cassettes 16 may be front opening unified pods (FOUPs).

FIG. 4 depicts a part of the cassette storage carousel 18 of FIGS. 1 to 3. The cassette storage carrousel 18 functioning as the rotatable table may comprise a central vertical frame 71 supporting a number of platform stages 70. The central vertical frame 71 and the platform stages 70 may be rotatable around a substantially vertical axis perpendicular to the table. The platform stages 70 may support a number of wafer cassettes (not shown). The substantial vertical axis may be off center with respect to a wafer supported on the table.

Each cassette storage carousel 18 may further comprise a drive assembly 72 mounted on the stationary frame 74. The drive assembly 72 may be operatively connected to the central vertical frame 71 via a driving wheel and a driving belt 73 for driving the central vertical frame 71 with the number of platform stages 70 around the substantially vertical axis.

The apparatus may be provided with a supply line 76 to supply a utility to the central vertical frame 71 and the platform stages 70. The drive assembly 72 may be controlled and configured to create the rotary movement of the central vertical frame 71 and the platform stages 70 in a clockwise and/or an anticlockwise direction 77 to avoid breakage of the supply line 76.

According to an embodiment the drive assembly 72 may be controlled and configured to create the rotary movement in at least one of the clockwise and anticlockwise direction 77 over a maximal first angle. The maximal first angle may be for example 180 to 260, preferable 270 degrees. After this rotation, the supply line 76 may be stretched to a maximum so that the rotary direction may need to be changed.

The drive assembly 72 may therefore be controlled and configured to change the rotary direction to the other than said one of the clockwise and anticlockwise direction. The drive assembly 72 may be controlled and configured to create the rotary movement in the other than said one of the clockwise and anticlockwise direction over a second angle. The second angle may be for example 180 to 260, preferable 270 degrees in the other than said one of the clockwise and anticlockwise direction. After this movement the supply line 76 may be stretched to a maximum so that the rotary direction may need to be changed again. The drive assembly may be controlled and configured to change the rotary direction to said one of the clockwise and anticlockwise direction again.

According to an embodiment the utility may be a fluid. The supply line 76 may be hollow and constructed and arranged to supply the fluid to the table from a fluid supply of the apparatus.

According to an embodiment the fluid may be a purge gas and the supply line may be connected to a purge gas supply of the apparatus. The apparatus may be provided with a cassette storage carousel 18 functioning as a rotatable table. The cassette storage carousel may comprise a number of platform stages 70 constructed and arranged to support a plurality of wafer cassettes. The supply line may be operably connected to a plug 75 to provide purge gas to a cassette, e.g., FOUP, supported on a platform stage 70 to purge the wafers in the cassette when it is supported on the platform stage 70.

According to an embodiment the supply line 76 may comprise a flexible material to allow for the rotary movement.

According to an embodiment the supply line 76 may be curled to allow for the rotary movement.

According to an embodiment the fluid may be a cooling liquid and the supply line 76 may be operably connected to a cooling liquid supply of the apparatus. Water may be used as a cooling liquid in the apparatus and the supply line 76 may be operably connected to a water cooler.

According to an embodiment the utility may be electricity and the supply line 76 may comprises a metal core to supply the electricity to the table from a power supply of the apparatus. In the same manner electrical data signals may be transmitted between the rotating table and a controller via a supply line 76 with the metal core.

Alternatively, the supply line 76 may be used for optical data transmission between the rotatable table and a controller. An optical transmissive core may therefore be provided to the supply line 76.

In an embodiment, of which an example is shown in FIGS. 5 and 6, the wafer processing apparatus 10 may be provided with a substantially rectangular footprint having two opposite short sides 66 defining a width of the wafer processing apparatus and having two opposite long 68 sides defining a length of the apparatus. The wafer processing apparatus 10 may further comprise at least one cassette in-out port 48, which may be arranged at one of the short sides 66 of the wafer processing apparatus 10. The wafer processing apparatus preferably comprises two cassette in-out ports 48, which may be arranged adjacent to each other.

The wafer processing apparatus 10 may further comprise a cassette storage 14 configured to store a plurality of substrate cassettes each of which comprises wafers. The apparatus may include a cassette door opener device 54 and a cassette handler 62 which may be configured to transfer substrate cassettes between the cassette in-out port 48, the cassette storage 14 and the door opener device 54. The cassette storage 14 may be embodied as a cassette storage carousel 18. The wafer processing apparatus 10 may comprise one, or multiple cassette storage carousels 18, as is shown in FIGS. 1 and 2. The wafer processing apparatus 10 may also comprise a wafer handler 64 configured to transfer wafers between a cassette in the door opener device 54 and a boat 12 b in the wafer boat handling device 11.

By having a substantially rectangular footprint and by having the cassette in-out port 48 arranged at the short side 66 of the apparatus 10, multiple of wafer processing apparatus 10 can be placed adjacent to each other. The cassettes with wafers to be processed can be transferred to and from the apparatus at the short side 66 of the vertical batch furnace 10. The other parts of the assembly 10 may be arranged in cascade behind the in-out port 48 such that the wafer processing apparatus10 may have a certain maximum width. A width of less than 1100 mm is beneficial in view of interchangeability with other vertical batch furnace assemblies.

The present disclosure also provides a wafer processing apparatus 10 comprising a process chamber 56 for processing wafers accommodated in a wafer boat, and a wafer boat handling device 11 according to the present disclosure. The wafer boat handling device 11 is positioned under the process chamber 56, and is provided with a wafer boat elevator 40 configured to transfer a wafer boat 12 from the wafer boat handling device 11 to the process chamber 56 and vice versa.

The effects and advantages of the wafer processing apparatus have been described in the summary section and these effects and advantages are inserted here by reference.

Finally, the present disclosure provides a method for handling wafer boats 12. The method comprises:

providing a wafer processing apparatus 10 comprising a process chamber 56 and a wafer boat handling device 11 which is positioned under the process chamber 56;

providing the first wafer boat support surface with an associated first wafer boat 12 a loaded with wafers and the second wafer boat support surface with an associated second wafer boat 12 b loaded with wafers;

loading the first wafer boat 12 a vertically from the first wafer boat support surface which is in the load/receive position into the process chamber 56; and processing the wafers accommodated in the first wafer boat 12 a in the process chamber 56, whilst simultaneously:

cooling down the second wafer boat 14 on the second wafer boat support surface in a cooldown position;

subsequent to the cooling down, rotate the rotatable table 34 to a position in which the second wafer boat support surface is in the transfer position;

transferring wafers to and/or from the second wafer boat 12 b; and

subsequent to the transferring, rotate the rotatable table 34 to a position in which the first wafer boat support surface is in the load/receive position.

The effects and advantages of the method have been described in the summary section and these effects and advantages are inserted here by reference.

In an embodiment, the method may further comprise:

receiving the first wafer boat 12 a from the process chamber 56 on the first wafer boat support surface 18; and

subsequently rotate the rotatable table 34 to a rotational position in which the second wafer boat support surface is in the load/receive position.

The apparatus may have a cassette storage 60 and a cassette handler 62 configured to transfer wafer cassettes between the cassette storage and a wafer transfer position and a wafer handler 64 configured to transfer wafers between a wafer cassette in the wafer transfer position and a wafer boat 12 b in a wafer boat transfer position.

The rotatable table 34 may be constructed and arranged to support the boat 12 a, b in the wafer boat transfer position. The apparatus may have a wafer boat elevator position and the rotatable table 34 may be constructed and arranged to rotate the boat 12 a, b from the wafer boat transfer position to the wafer boat elevator position. The apparatus may be provided with a supply line to supply a utility to the rotatable table 34. The supply line may be curled and /or from flexible material to allow for rotation. The utility may be cooling water. The apparatus may comprise a drive assembly controlled and configured to create the rotary movement of the table 34 in two directions e.g. a clockwise and/or an anticlockwise direction to avoid breakage of the supply line.

The apparatus may comprises a process chamber 56 constructed and arranged to process a plurality of wafers supported in a wafer boat 12 a, b. The wafer boat elevator 40 may transfer the boat 12 a, b between the wafer boat elevator position and the process chamber 56.

In an embodiment the rotatable table may be constructed and arranged to support and rotate the wafer boat 12 a, b with a plurality of wafers within the process chamber 54. The rotatable table may be rotatable around an axis perpendicular to the table. The axis may be substantially through the center of a wafer supported on the table. The apparatus may be provided with a supply line to supply a utility to the rotatable table. The supply line may be a power cable to power an electrical heater. The supply line may be curled and /or from flexible material to allow for rotation. The apparatus may comprise a drive assembly controlled and configured to create the rotary movement of the wafer boat in a clockwise and/or an anticlockwise direction to avoid breakage of the supply line.

Although illustrative embodiments of the present invention have been described above, in part with reference to the accompanying drawings, it is to be understood that the invention is not limited to these embodiments. Variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims.

Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this description are not necessarily all referring to the same embodiment.

Furthermore, it is noted that particular features, structures, or characteristics of one or more of the various embodiments which are described above may be used implemented independently from one another and may be combined in any suitable manner to form new, not explicitly described embodiments. The reference numbers used in the detailed description and the claims do not limit the description of the embodiments nor do they limit the claims. The reference numbers are solely used to clarify. 

What is claimed is:
 1. A wafer processing apparatus for processing wafers comprising: a rotatable table provided with a support constructed and arranged to support a removable holder for holding a plurality of wafers; and, a drive assembly to provide a rotary movement to the rotatable table around a substantially vertical axis substantially perpendicular to the table; wherein the apparatus is provided with a supply line to supply an utility to the rotatable table and the drive assembly is controlled and configured to create the rotary movement of the table in two directions, clockwise and anticlockwise, to avoid breakage of the supply line.
 2. The apparatus according to claim 1, wherein the drive assembly is controlled and configured to create the rotary movement in one of the clockwise and anticlockwise direction over a first angle.
 3. The apparatus according to claim 2, wherein the drive assembly is controlled and configured to change the rotary direction to the other than said one of the clockwise and anticlockwise direction when the rotary movement in said one of the clockwise and anticlockwise direction reaches the first angle.
 4. The apparatus according to claim 2, wherein the drive assembly is controlled and configured to create the rotary movement in the other than said one of the clockwise and anticlockwise direction over a second angle equal but opposite to the first angle.
 5. The apparatus according to claim 4, wherein the drive assembly is controlled and configured to change the rotary direction to said one of the clockwise and anticlockwise direction again when the rotary movement in said other then said the one of the clockwise and anticlockwise direction reaches the second angle.
 6. The apparatus according to claim 1, wherein the utility is a fluid and the supply line is hollow and constructed and arranged to supply the fluid to the table from a fluid supply of the apparatus.
 7. The apparatus according to claim 6, wherein the fluid is a purge gas and the supply line is connected to a purge gas supply of the apparatus.
 8. The apparatus according to claim 7, wherein the apparatus is provided with a cassette storage comprising the rotatable table as a cassette storage carousel constructed and arranged to support a plurality of wafer cassettes and the supply line is operably connected to a plug to provide purge gas to the cassette.
 9. The apparatus according to claim 6, wherein the fluid is a cooling liquid and the supply line is operably connected to a cooling liquid supply of the apparatus.
 10. The apparatus according to claim 1, wherein the utility is electricity and the supply line comprises a metal core and is constructed and arranged to supply the electricity to the table from a power supply of the apparatus.
 11. The apparatus according to claim 1, wherein the supply line is curled to allow for the rotary movement.
 12. The apparatus according to claim 1, wherein the supply line comprises a flexible material to allow for the rotary movement.
 13. The apparatus according to claim 1, the apparatus comprises: a cassette storage and a cassette handler configured to transfer wafer cassettes between the cassette storage and a wafer transfer position; and, a wafer handler configured to transfer wafers between a wafer cassette in the wafer transfer position and a wafer boat in a wafer boat transfer position, wherein the rotatable table is constructed and arranged to support the boat in the wafer boat transfer position.
 14. The apparatus according to claim 13, wherein the apparatus comprises a wafer boat elevator position and the rotatable table is constructed and arranged to rotate the boat from the wafer boat transfer position to the wafer boat elevator position.
 15. The apparatus according to claim 14, wherein the apparatus comprises a process chamber and an elevator to transfer the boat between the wafer boat elevator position and the process chamber.
 16. The apparatus according to claim 1, wherein the apparatus comprises a process chamber constructed and arranged to process a plurality of wafers supported in a wafer boat.
 17. The apparatus according to claim 16, wherein the rotatable table is constructed and arranged to support and rotate the wafer boat within the process chamber.
 18. The apparatus according to claim 16, wherein the rotatable table is constructed and arranged to support and rotate a plurality of wafers outside the process chamber.
 19. The apparatus according to claim 1, wherein the rotatable table is rotatable around the substantially vertical axis perpendicular to the table, wherein the substantially vertical axis is off center with respect to a wafer supported on the table.
 20. The apparatus according to claim 1, wherein the rotatable table is rotatable around a substantially vertical axis perpendicular to the table, wherein the vertical axis is substantially through the center of a wafer supported on the table. 